The correct answer is C, the Cx agent for the project must conduct or oversee the Cx of the PV system. According to the LEED v4 Reference Guide for Building Design and Construction, the Energy and Atmosphere Prerequisite, Fundamental Commissioning and Verification, requires that all energy-related systems, including renewable energy systems such as PV, be commissioned by an independent commissioning agent (CxA) or a qualified member of the project team who reports to the owner. The CxA or the qualified team member must perform or oversee all commissioning activities, including developing a commissioning plan, reviewing design documents and submittals, verifying installation and performance, and preparing a commissioning report12 Reference: 1: LEED v4 Reference Guide for Building Design and Construction, Energy and Atmosphere Prerequisite: Fundamental Commissioning and Verification, page 562. 2: LEED v4 Reference Guide for Building Design and Construction, Glossary, page 1020.

Explanation
According to the LEED v4: Building Design + Construction Guide, the Sustainable Sites Credit, Open Space requires the project to provide outdoor space greater than or equal to 30% of the total site area (including building footprint). At least 25% of that outdoor space must be vegetated, have overhead vegetated canopy, or be a water body. Option A does not qualify as outdoor space, Option B is not vegetated or a water body, and Option C only applies to projects with a FAR of less than 1.0. Option D meets the requirements for both outdoor space and vegetation, and also contributes to the protection or restoration of habitat1. References:
LEED v4: Building Design + Construction Guide, Sustainable Sites Credit, Open Space, Requirements1

Minimum Energy Performance
A project's massing and site orientation can have a direct impact on the minimum energy performance prerequisite, which requires projects to demonstrate a percentage of energy cost savings compared to a baseline building. Massing and orientation affect the amount of solar heat gain, daylight availability, natural ventilation potential, and wind exposure of the building, which in turn influence the heating, cooling, lighting, and ventilation loads and strategies. By optimizing the massing and orientation of the building, projects can reduce their energy consumption and improve their thermal and visual comfort.
References:
* Reference Guide for Building Design and Construction v4 - Pages 279-2801
* Building Massing & Orientation | Sustainability Workshop2

The referenced standard for Indoor Environmental Quality (IEQ) Prerequisite: Minimum Indoor Air Quality (IAQ) Performance in LEED AP ID+C projects is ASHRAE 62.1 - 2010. ASHRAE 62.1 specifies ventilation rates and air quality requirements for acceptable indoor air quality in commercial buildings, establishing the minimum standards needed to maintain health and comfort. ASHRAE 62.2 (A) is relevant to low-rise residential buildings, ASHRAE 90.1 (B) covers energy standards, and ASHRAE 55 (C) relates to thermal comfort rather than air quality.

The basis of energy consumption in determining the percentage of green power or carbon offsets is the quantity of energy used by the project, measured in kilowatt-hours (kWh) or British thermal units (Btu).
Green power is electricity generated from renewable sources, such as solar, wind, hydro, biomass, or geothermal. Carbon offsets are reductions or removals of greenhouse gas emissions from a project or activity that compensates for the emissions from another source. According to the LEED Reference Guide for Building Design and Construction1, the Energy and Atmosphere Credit, Green Power and Carbon Offsets, requires the project to engage in a contract for qualified resources that meet the following requirements:
* The contract term is at least five years.
* The green power or carbon offsets are based on the quantity of energy consumed by the building.
* The green power is Green-e Energy certified or the equivalent.
* The carbon offsets are Green-e Climate certified, Verified Carbon Standard certified, Gold Standard certified, or the equivalent.
References:
* LEED Reference Guide for Building Design and Construction v4
* Green Power and Carbon Offsets | U.S. Green Building Council
* Green Power and Carbon Offsets - LEEDuser
* Green Power and Carbon Offsets - LEED v4 for BD+C: New Construction ...